Heart valve docking devices and implanting methods

ABSTRACT

A device is in various embodiments configured to repair a native heart valve or to secure a prosthetic heart valve within a native valve of the heart of a patient. Embodiments of the device include at least an upper coil and a lower coil, where the device is configured to assume an axially expanded state where the entire upper coil is positioned on a first side of the lower coil relative to the central axis, and an axially compressed state where at least a portion of the upper coil is positioned on a second side of at least a portion of the lower coil opposite to the first side relative to the central axis.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to and the benefit of U.S. ProvisionalPatent Application Ser. No. 62/115,010, filed Feb. 11, 2015, thecontents of which are hereby incorporated by reference in theirentirety.

BACKGROUND

Field

The present disclosure generally concerns prosthetic heart valves andassociated devices and related methods for implanting such devices. Morespecifically, the disclosure relates to the repair and replacement ofheart valves that have malformations and/or dysfunctions, where anadditional dock or anchor is utilized together with the prosthetic heartvalve at the implant site, and methods of implanting such anchors and/orprosthetic heart valves.

Description of Related Art

Referring generally to FIGS. 1A-1B, the native mitral valve controls theflow of blood from the left atrium to the left ventricle of the humanheart. The mitral valve has a very different anatomy than other nativeheart valves. The mitral valve includes an annulus made up of nativevalve tissue surrounding the mitral valve orifice, and a pair of cuspsor leaflets extending downward from the annulus into the left ventricle.The mitral valve annulus can form a “D” shaped, oval shaped, orotherwise non-circular cross-sectional shape having major and minoraxes. An anterior leaflet can be larger than a posterior leaflet of thevalve, forming a generally “C” shaped boundary between the abutting freeedges of the leaflets when they are closed together.

When operating properly, the anterior leaflet and the posterior leafletof the mitral valve function together as a one-way valve to allow bloodto flow only from the left atrium to the left ventricle. After the leftatrium receives oxygenated blood from the pulmonary veins, the musclesof the left atrium contract and the left ventricle dilates (alsoreferred to as “ventricular diastole” or “diastole”), and the oxygenatedblood that is collected in the left atrium flows into the leftventricle. Then, the muscles of the left atrium relax and the muscles ofthe left ventricle contract (also referred to as “ventricular systole”or “systole”), to move the oxygenated blood out of the left ventricleand through the aortic valve to the rest of the body. The increasedblood pressure in the left ventricle during ventricular systole urgesthe two leaflets of the mitral valve together, thereby closing theone-way mitral valve so that blood cannot flow back into the leftatrium. To prevent the two leaflets from prolapsing under the pressureand folding back through the mitral annulus toward the left atriumduring ventricular systole, a plurality of fibrous cords called chordaetendineae tether the leaflets to papillary muscles in the leftventricle.

One common form of valvular heart disease is mitral valve leak, alsoknown as mitral regurgitation. Mitral regurgitation occurs when thenative mitral valve fails to close properly and blood flows back intothe left atrium from the left ventricle during the systolic phase ofheart contraction. Mitral regurgitation has different causes, such asleaflet prolapse, dysfunctional papillary muscles, and/or stretching ofthe mitral valve annulus resulting from dilation of the left ventricle.In addition to mitral regurgitation, mitral narrowing or stenosis isanother example of valvular heart disease.

Like the mitral valve, the aortic valve is susceptible to complicationssuch as aortic valve stenosis. One method for treating such valvularheart disease includes the use of a prosthetic valve implanted withinthe native heart valve. These prosthetic valves can be implanted using avariety of techniques, including various transcatheter techniques. Onetranscatheter technique that is commonly used for accessing a nativevalve is the transseptal technique, where a catheter accesses the leftside of the heart via a femoral vein, the inferior vena cava, the rightatrium, and then a puncture hole in the interatrial septum. A prostheticvalve can then be mounted in a crimped state on the end portion of asecond, flexible and/or steerable catheter, advanced to the implantationsite, and then expanded to its functional size, for example, byinflating a balloon on which the valve is mounted. Alternatively, aself-expanding prosthetic valve can be retained in a radially compressedstate within a sheath of a delivery catheter, and the prosthetic valvecan be deployed from the sheath, which allows the prosthetic valve toexpand to its functional state.

Another common transcatheter technique for implanting a prosthetic valveis a transventricular approach, where a small incision is made in thechest wall and the ventricular wall of a patient, and then a catheter orintroducer sheath is inserted into the left ventricle. A deliverycatheter containing or holding the prosthetic valve can then be advancedthrough the introducer sheath to the implantation site.

Such prosthetic valves are generally better developed for implantationor use at the aortic valve. However, similar catheter-based prostheticvalves can be more difficult to apply or implant at the native mitralvalve due to the structural differences between the aortic and mitralvalves. For example, the mitral valve has a more complex subvalvularapparatus, which includes the chordae tendineae. Additionally, thenative mitral valve is less circular in shape and typically does notprovide sufficient structure for anchoring and resisting migration of aprosthetic valve.

SUMMARY

Since many valves have already been developed for the aortic position,it would be desirable to try to take advantage of these existing valvetechnologies and to utilize the same or similar valves for tricuspid,pulmonic and mitral valve replacements. One way of utilizing thesepreexisting prosthetic valves is to use the prosthetic valves togetherwith an anchor or other docking station that will form a moreappropriately shaped implant site at the native valve annulus, so thatthe prosthetic valve can be implanted more securely, while reducing oreliminating leakage around the valve after implantation. For example, amitral anchor or docking station can form a more circular bore at theannulus to more closely match the circular profiles of existing aorticvalve implants. In this manner, an existing valve implant developed forthe aortic position, perhaps with some modification, could then beimplanted at the mitral position together with such an anchor. Inaddition, such anchors could also potentially be used at the heart'sother native valves to more securely anchor prosthetic valves at thosesites as well.

Described herein are embodiments of prosthetic devices that areprimarily intended to be implanted at one of the native mitral, aortic,tricuspid, or pulmonary valve regions of a human heart, as well asapparatuses and methods for implanting the same. The prosthetic devicescan be used to repair the native valve annulus, as well as to positionand secure a prosthetic heart valve in the native valve region. Thedisclosed devices can include a helical anchor having a plurality ofturns or coils, where the helical anchor can assume an axially collapsedposition where portions of at least two of the coils align or overlap ina radial direction.

In one embodiment, a helical device for implanting at a native heartvalve of a heart of a patient includes an upper coil and a lower coil,and a central axis extending through the upper coil and the lower coil.The device is configured to assume an axially expanded state where theentire upper coil is positioned on a first side of the lower coilrelative to the central axis, and is also configured to assume anaxially compressed state where at least a portion of the upper coil ispositioned on a second side of at least a portion of the lower coilopposite to the first side relative to the central axis. The device caninclude a first set of one or more coils comprising the upper coilhaving a first inner diameter, and a second set of one or more coilscomprising the lower coil having an inner diameter different from thefirst inner diameter.

In certain embodiments, the device can include a first set of coilshaving at least two coils and a second set of coils having at least twocoils. At least one of the coils of the first set of coils is positionedrelative to the central axis between two coils of the second set ofcoils when the device is in the compressed state. The first set of coilscan be configured to be positioned on a ventricular side of a nativevalve, and the second set of coils can be configured to be positioned onan atrial side of the native valve. Preferably, the upper and lowercoils are made from a shape-memory material, such a Nitinol.

In another embodiment, a method of implanting a helical device,including an upper coil and a lower coil, at a native valve of a heartof a patient, involves positioning the lower coil on a ventricular sideof the native valve, positioning the upper coil on an atrial side of thenative valve, such that the entire upper coil is positioned on a firstside of the lower coil relative to a central axis of the device, andadjusting the device to a position where at least a portion of the uppercoil is positioned on a second side of at least a portion of the lowercoil opposite to the first side relative to the central axis.

The method can include implanting a prosthetic heart valve within thedevice. The prosthetic heart valve is positioned in the device when theprosthetic heart valve is in a radially compressed state, and theprosthetic heart valve is radially expanded such that a radial pressureis applied between the prosthetic heart valve and the device to anchorthe prosthetic heart valve within the device

In another embodiment, a system for securing a prosthetic heart valve ata native heart valve of a heart of a patient includes a helical dockingdevice including an upper coil and a lower coil, where a central axisextends through the upper coil and the lower coil, and a prostheticheart valve configured to be held in the docking device. The dockingdevice is configured to assume an axially expanded state where theentire upper coil is positioned on a first side of the lower coilrelative to the central axis, and is also configured to assume anaxially compressed state where at least a portion of the upper coil ispositioned on a second side of at least a portion of the lower coilopposite to the first side relative to the central axis. The system caninclude a delivery catheter configured to deploy the docking device atthe native heart valve.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing and other objects, features, and advantages of theinvention will become more apparent from the following detaileddescription using the accompanying figures. In the drawings:

FIG. 1A shows a schematic cross-sectional view of a human heart;

FIG. 1B shows a schematic top view of the mitral valve annulus of aheart;

FIGS. 2A-2C respectively show a perspective view, a side view, and a topview of a helical device according to a first embodiment of theinvention;

FIGS. 3A and 3B respectively show a perspective view and across-sectional view of a compressed state of the helical device ofFIGS. 2A-2C;

FIGS. 4A-4M show one embodiment of a delivery apparatus and method forimplanting a helical docking device and a prosthetic valve at the nativemitral valve of a heart, using a transventricular technique;

FIGS. 5A-5E show another embodiment of a delivery apparatus and methodfor implanting a helical device at the native mitral valve of a heart,using a transseptal technique;

FIG. 6A shows a perspective view of a helical docking device accordingto a second embodiment of the invention;

FIGS. 6B-6D show various cross-sectional views of the helical dockingdevice of FIG. 6A implanted at the native mitral valve of a heart;

FIG. 7A shows a perspective view of an expanded state of a helicaldocking device according to a third embodiment of the invention;

FIGS. 7B and 7C show cross-sectional views of the helical docking deviceof FIG. 7A at the native mitral valve of a heart;

FIG. 8A shows a perspective view of an expanded state of a helicaldocking device according to a fourth embodiment of the invention;

FIGS. 8B and 8C show cross-sectional views of the helical docking deviceof FIG. 8A at the native mitral valve of a heart; and

FIGS. 9A-9C show perspective views of a portion of a delivery catheterfor a helical docking device, according to one embodiment.

DETAILED DESCRIPTION

Described herein are embodiments of prosthetic devices that areprimarily intended to be implanted at one of the native mitral, aortic,tricuspid, or pulmonary valve regions of a human heart, as well asapparatuses and methods for implanting the same. The prosthetic devicescan be used to repair a native valve and to position and secure aprosthetic heart valve in the native valve region. These prostheticdevices can improve the functionality of the prosthetic heart valves, inorder to better repair replace or replicate the functionality of adefective native heart valve. The present disclosure is directed towardall features and aspects of the various disclosed embodiments, bothalone and in various combinations and sub-combinations with one another.

In particular embodiments, a prosthetic assembly includes an anchoringor docking device configured to be implanted at or adjacent the nativevalve and configured to receive and retain a prosthetic valve. Thedocking device can be delivered and implanted in a minimally invasivemanner via the left ventricle and/or the left atrium, after which aseparate prosthetic valve can be delivered and implanted within thedocking device in a minimally invasive manner.

In particular embodiments, a docking device includes a helical anchorhaving a plurality of turns or coils with at least one of the coilshaving a negative pitch relative to an adjacent coil when the helicalanchor is in at least one state, for example, its undeformed ornon-tensioned state. As used herein, the “pitch” of a helical anchor isthe distance from the center of one coil to the center of an adjacentcoil. In a typical helix, the coils extend in a same axial direction,such that each coil can be said to have a positive pitch with respect toa preceding coil in this axial direction. However, if one of the turnsor coils doubles over on an outside or an inside of its preceding coil,then it could be said that that particular coil extends in a directionopposite to the positive axial direction, making the pitch of that coil“negative” relative to its preceding coil. Thus, a coil with a “negativepitch” extends along the longitudinal axis of the helical anchor in adirection opposite to the direction of extension of the other coils inthe helical anchor. In some embodiments, a helical anchor can bepre-formed with at least one coil having a negative pitch relative toother coils in the anchor when the anchor is in its undeformed ornon-tensioned state. In these embodiments, when the helical anchor isheld in a tensioned stated, the pitch as measured from a first coil to asecond coil extends in a first direction and defines a positive pitch,and when the helical anchor is released from the tensioned state, thesecond coil can move axially back towards and past the first coil, suchthat the second coil extends in the opposite direction and defines anegative pitch. As such, the first coil can be disposed at leastpartially within (i.e., radially inward from) the second coil, or viceversa, in such a non-tensioned state. The anchor can be adjusted to itsfinal position by self-aligning or by being guided or installed by thedelivery system.

FIGS. 2A-3B show a helical docking device 34 according to a firstembodiment of the invention. The docking device 34 includes first andsecond lower or ventricular coils 54 a, 54 b configured to be positionedon the ventricular side of the native valve, and first and second upperor atrial coils 56 a, 56 b configured to be positioned on the atrialside of the native valve. Although the illustrated docking device 34 hastwo ventricular coils and two atrial coils, other embodiments of thedocking device can have a greater or fewer number of ventricular coilsand/or atrial coils.

In the embodiment of FIGS. 2A-3B, the atrial coils 56 a, 56 b have aninner diameter that is different than the inner diameter of theventricular coils 54 a, 54 b, to facilitate nesting or positioning ofthe atrial coils within the ventricular coils when the docking device 34is in a compressed state. As shown in FIGS. 2B-2C, the atrial coils 56a, 56 b have an inner diameter 72 that is less than the inner diameter74 of the ventricular coils 54 a, 54 b. Larger ventricular coils can,for example, make it easier to loop the ventricular coils 54 a, 54 baround the leaflets of the native mitral valve and/or the chordaetendineae. Larger ventricular coils can also, for example, allow thedocking device and a docked prosthetic heart valve to be placed higherin the native valve (i.e., towards the atrium), as further describedbelow.

The atrial coils 56 a, 56 b can have an inner diameter 72 of about 22 mmto about 30 mm, with about 25 mm being a specific example. Theventricular coils can have an inner diameter 74 of about 24 mm to about32 mm, with about 27 mm being a specific example. The coil wire can havea diameter of about 0.3 mm to about 1.2 mm, with about 1 mm being aspecific example. When the docking device 34 is in the axiallycompressed state (e.g., as seen in FIGS. 3A-3B), the innermost diameterof the docking device can be about 25 mm, and the outermost diameter ofthe docking device can be about 29 mm. The prosthetic valve 36 can beselected to have a nominal outer diameter that is slightly larger thanthe innermost diameter of the docking device to create sufficientanchoring force between the prosthetic valve and the docking device inthe radial direction to hold the prosthetic valve in place. For example,a docking device having the dimensions provided above can be used with a26 mm prosthetic valve.

In alternative embodiments, the inner diameter of the atrial coils canbe greater than the inner diameter of the ventricular coils (e.g., asseen in FIGS. 6A-6D, described in greater detail below).

In particular embodiments, the inner diameter of each ventricular coilcan be substantially the same, and/or the inner diameter of each atrialcoil can be substantially the same. As such, when the docking device 34moves from the axially expanded state to the axially compressed state,as further described below, the ventricular coils 54 a, 54 b axiallyoverlap with the atrial coils 56 a, 56 b in a manner similar to acylinder within a cylinder.

In other embodiments, the inner diameter of each of the atrial andventricular coils can vary. For example, an atrial coil can have aninner diameter that is greater than or less than the inner diameter ofanother atrial coil, and a ventricular coil can have an inner diameterthat is greater than or less than the inner diameter of anotherventricular coil. In addition, one or more atrial coils can have aninner diameter that is the same as one or more ventricular coils.

In one embodiment, docking device 34 is axially expandable when tensionis applied to one or both ends of the docking device 34, and is axiallycompressible when tension is released from the docking device 34. Inthis manner, the docking device 34 can be said to be made up of or actsimilarly to a tension spring. FIGS. 2A-2C show the docking device in anaxially expanded state such that all the coils have a positive pitchwith respect to adjacent coils. That is, the second ventricular coil 54b is located upstream of the first ventricular coil 54 a in the axialdirection (i.e., upwards as illustrated), the first atrial coil 56 a islocated upstream of the second ventricular coil 54 b, and the secondatrial coil 56 b is located upstream of the first atrial coil 56 a.Therefore, in this embodiment, a positive pitch direction can be definedas being oriented in the upstream or upwards direction.

Meanwhile, FIGS. 3A-3B show the docking device 34 in an axiallycompressed state, for example, after tension is released from thedocking device 34. In this state, the first atrial coil 56 a moves, oris activated by a delivery system, axially past the center of the secondventricular coil 54 b in the downstream direction (i.e., downwards asillustrated), such that the first atrial coil 54 a is located below thesecond ventricular coil 54 b (and between the first ventricular coil 54a and the second ventricular coil 54 b in the embodiment shown). Thus,the first atrial coil 56 a can be said to be positioned at a negativepitch with respect to the second ventricular coil 54 b. Additionally, inthe compressed state, the atrial coils 56 a, 56 b are located radiallyinward of the ventricular coils 54 a, 54 b. As shown, the atrial coils56 a, 56 b become interlaced and nest within the ventricular coils 54 a,54 b.

By virtue of the docking device 34 assuming the axially compressed stateshown in FIGS. 3A-3B, the native valve leaflets can become capturedbetween the ventricular coils 54 a, 54 b and the atrial coils 56 a, 56 b(see, e.g., FIGS. 4L and 4M), with the coils compressing or pinching theleaflets between adjacent coils in the radial direction, and in somecases in the axial direction as well. The docking device 34 exertssufficient force against the native leaflets to retain the dockingdevice 34 in place and resist migration due to the flow of blood betweenthe left atrium and the left ventricle, before a prosthetic heart valveis implanted within the docking device 34. Because the docking device 34can be secured to the valve leaflets without needing to be held in placeby a delivery apparatus or other device, the delivery apparatus can beremoved from the patient's heart prior to deploying a prosthetic heartvalve within the docking device 34, as further described below. Thiscan, for example, advantageously reduce the complexity of the entireprocedure of implanting the docking device and the prosthetic heartvalve thereafter.

Since at least some coils of the docking device 34 axially overlap(similar to a spring within a spring) the docking device can be formedfrom a relatively thin wire. This is because together, theaxially-overlapping coils provide sufficient radial force to securelyhold a prosthetic heart valve in place during the dynamic diastolic andsystolic phases of heart contraction. Forming the docking device from arelatively thin wire can, for example, make the docking device 34 easierto deliver through a delivery apparatus and can facilitate deploymentfrom the delivery apparatus.

The docking device 34 can be shaped or otherwise formed from a piece ofwire, tube, or strip of material that is made from a flexible, elastic,resilient material such as Nitinol, stainless steel, or a polymer thatreturns to its original shape when released from a deformed or deflectedstate. Coil flexibility can also, for example, be achieved by using anarrow or thin spring, applying notches to a thin tube, or using abraided material. In some embodiments, the docking device can be loadedinto the shaft of a delivery catheter and retained in a substantiallystraight configuration within the delivery catheter for delivery intothe heart of a patient. When formed from a flexible, elastic, resilientmaterial, the docking device 34 can be formed or shape-set (e.g., byheat-shaping a Nitinol wire) in the helical, axially compressed stateshown in FIG. 3A. In this manner, the docking device 34 can transitionfrom the substantially straight configuration to its coiledconfiguration after it is released from the delivery catheter.

As shown, the coil wire of docking device 34 has a generally circularcross-sectional shape. In other embodiments, the coil wire can includevarious other cross-sectional shapes, such as square, rectangular,elliptical, etc. For example, the coil wires of docking device 300 anddocking device 400 (see FIGS. 7A-7C and 8A-8C) have a generallyrectangular cross-sectional shape.

It should be noted that a docking device can be formed from one or morehelically-shaped pieces of wire, tubes, or strips of material. Forexample, in some embodiments, the ventricular coils and the atrial coilscan be formed from one continuous piece of wire. In other embodiments,the ventricular coils can be formed from a first piece of wire ormaterial, and the atrial coils can be formed from a second, separatepiece of wire or material. When the docking device is formed from two ormore pieces of wire or material, each piece of the docking device can,for example, be deployed using the same delivery apparatus or usingseparate delivery apparatuses.

In embodiments discussed above, at least part of a first set of coilsbecomes nested within a second set of coils, where at least a portion ofone or more coils of the second set align or overlap with one or morecoils of the first set in a radial direction, for example, by virtue ofreleasing tension on the docking device and allowing the device toassume a shape-memory state. In other embodiments, a docking device canbe configured such that the atrial coils and the ventricular coils donot revert to a nested configuration when tension is released from thedocking device. Instead, the docking device can be configured such thata first set of coils are manually moved to an axial position where oneor more coils of the second set overlap one or more coils of the firstset in the radial direction, such as by application of an axiallydirected force to one or both ends of the docking device. In theseembodiments, the docking device can, for example, be forced into thenested or radially overlapping state by manually applying a force (e.g.,an axially compressive force) to the docking device with a deliveryapparatus.

FIGS. 4A-4M show a method of implanting a docking device 34 and aprosthetic heart valve 36 at a native mitral valve 42 of a patient'sheart 12 with a delivery apparatus 10, according to one embodiment thatuses a transventricular technique.

As shown in FIG. 4A, the delivery apparatus 10 includes an introducer 14and a flexible delivery catheter 16 (also referred to as a “guidecatheter” in some embodiments). The introducer 14 of the deliveryapparatus 10 has an axially extending shaft portion 18 and a hub orhousing 20. The housing 20 is fixedly secured or coupled to the proximalend 24 of the shaft portion 18. The introducer 14 also has a lumen 22extending co-axially through the shaft 18 and the housing 20. Throughthe lumen 22 of the introducer 14, various other components of thedelivery apparatus 10 and/or other devices (prosthetic implants,catheters, etc.) can be introduced into the patient's heart 12. Thehousing 20 can also house one or more elastomeric seals to maintainhemostasis as devices are inserted through the lumen 22, as known in theart.

The guide catheter 16 of the delivery apparatus 10 includes an elongateshaft 25. The shaft 25 has a flexible section 26 extending along adistal portion of the shaft 25, a relatively more rigid section 30located adjacent and proximal to the flexible section 26, and a lumen 32that extends the length of the shaft 25.

The flexible section 26 of the shaft 25 can be positioned in a first,delivery configuration and a second, activated configuration. In thedelivery configuration, the flexible section 26 is substantiallystraight, allowing the flexible section 26 to easily pass through thelumen 22 of the introducer 14 and the mitral valve 42, as shown in FIG.4A. In the activated configuration, the guide catheter 16 forms a first,“U”-shaped curved portion 46 and a second, helically curved portion 48,as best shown in FIGS. 4B and 4C. The first curved portion 46 forms a180-degree bend at the end of the rigid section 30 and extendssubstantially parallel to the rigid section 30. The second curvedportion 48 includes a proximal section 48 a that curves radially awayfrom the first curved portion 46 in a plane that is substantiallyperpendicular to the first curved portion 46 and includes a distal tipportion 48 b that is angled downwardly away from the plane of theproximal section 48 a. These curved portions 46, 48 can help properlyposition the helical docking device 34 during the implantationprocedure, as further described below.

In one embodiment, the flexible section 26 of the shaft 25 can be formedfrom a flexible, elastic, resilient material such as Nitinol or apolymer that returns to its original shape when released from a deformedor deflected state. When formed from a resilient material, the flexiblesection 26 of the shaft 25 can be formed or shape-set (e.g., byheat-shaping a Nitinol tube) in the activated configuration (as seen inFIG. 4B). In this manner, the curved, activated configuration is theundeformed state of the flexible section, and therefore the flexiblesection will assume the activated configuration in the absence of anyexternal forces applied to the shaft.

Due to its flexible nature, the flexible section 26 of the shaft 25 canbe retained in the delivery configuration shown in FIG. 4A, for example,by inserting a rigid rod (not shown) through the lumen 32 of the shaft25. Inserting the rigid rod through the lumen 32 of the shaft 25 forcesthe flexible section 26 of the shaft 25 to axially elongate orstraighten, thus reducing the radial profile of the distal end of theguide catheter 16 compared to the radial profile of the distal end ofthe guide catheter 16 in the activated configuration. The deliveryconfiguration can allow the guide catheter 16 to move more easilythrough the patient's vasculature. Once the flexible section 26 of theshaft 25 has been advanced into the left atrium of the heart, the rigidrod can be retracted from within the flexible section 26 of the shaft25, which allows the flexible section 26 to return to its curved,activated configuration.

In an alternative embodiment, the flexible section 26 of the shaft 25can be placed in its activated configuration by one or more actuators orsteering mechanisms. For example, the flexible section 26 can beconverted from the delivery configuration to the activated configurationusing at least one pull wire (see, e.g., pull wire 104 in FIGS. 9A-9C).The pull wire can extend co-axially through the lumen 32 of the shaft 25and can have a distal end fixedly secured to the inner surface of thedistal end 28 of the shaft 25. The flexible section 26 of the shaft 25can be configured such that pulling on the proximal end of the pullwire, while maintaining the axial positioning of the guide catheter 16,applies an axially compressive force to the guide catheter 16. Thisaxially compressive force causes the flexible section 26 of the shaft 25of the guide catheter 16 to bend from the delivery configuration intothe activated configuration based, for example, on specific cuts orslots formed along the length of the shaft 25 to control the shaping ofthe flexible section 26.

In another embodiment, the docking device itself can be used to effectthe transition of the flexible section 26 of the shaft 25 from thedelivery configuration to the activated configuration. Once the guidecatheter 16 is advanced into the desired location for the placement ofthe docking device, the docking device can be advanced through the lumen32 of the shaft 25. In this alternative embodiment, the relatively morerigid section 30 of the shaft 25 can be configured to resist the springforce exerted by the docking device 34 (which is attempting to return toits undeformed, helical configuration), while the flexible section 26 ofthe shaft 25 can be configured to yield under the spring force exertedby the docking device 34. As a result, as the docking device 34 isadvanced through the lumen 32 of the shaft 25, the rigid section 30maintains its shape, while the flexible section 26 is caused to assumeits activated configuration under the force of the docking device 34.

In some embodiments, the flexible section 26 and the rigid section 30can be formed from the same material and/or formed from a single pieceof material (e.g., an alloy tube). When formed from the same materialand/or from a single piece of material, the shaft can be formed (e.g.,laser cut) with a series of slots in selected locations to impart adesired shape and degree of flexibility along certain portions of theflexible section and/or to achieve the curvature of the curved portions46, 48 when the shaft is in the activated configuration. In otherembodiments, the flexible section 26 and the rigid section 30 can beformed from different materials and/or formed from separate pieces ofthe same material that are fixedly secured or coupled together by anadhesive, welding, fasteners, etc. Materials having varying flexibilitycan be selected to form different sections of the shaft to achieve thedesired degree of flexibility for each section of the shaft.

Also, although not shown, it should be noted that the guide catheter 16can have multiple radial layers. For example, the delivery catheter 16can have an inner tube made of Nitinol, stainless steel, plastic, orother suitable material, that is surrounded by a polymeric cover (e.g.,PTFE). The delivery catheter 16 can also be formed from an alloy ormetal mesh or weave (e.g., braided Nitinol) having an inner and/or outerpolymeric liner. The interior of the delivery catheter can be lined witha lubricious material (e.g., PTFE) to allow the other devices to passmore easily through the lumen 32 of the shaft 25.

Referring back to FIGS. 4A-4C, the distal end 38 of the shaft 18 of theintroducer 14 can be inserted through the wall of the left ventricle 40,for example, at or near the apex of the heart, until the distal end 38is positioned in the left ventricle 40. The positioning of the deliveryapparatus 10 and later, the docking device 34 and the prosthetic valve36, can be confirmed visually, for example, by using imaging modalitiessuch as fluoroscopy, X-ray, CT, or MR imaging. Echocardiography ineither 2D or 3D can also be used to help guide and adjust thepositioning of the delivery apparatus 10, the docking device 34, and theprosthetic valve 36.

Although not shown, a standard purse string suture can be used to holdthe introducer 14 in place against the heart 12 and to prevent bloodleakage around the introducer 14, as well as to seal the opening in theheart 12 upon removal of the introducer 14. As noted above, theintroducer 14 can include an internal sealing mechanism (e.g.,hemostasis seal) to prevent blood leakage through the lumen 22 ofintroducer 14.

With the flexible section 26 of the shaft 25 in the deliveryconfiguration (i.e., straight or substantially straight), the deliverycatheter 16 can then be inserted into the patient's heart 12 byadvancing the distal end 28 of the shaft 25 through the lumen 22 of theintroducer 14, such that the flexible section 26 extends through theleft ventricle 40 and the mitral valve 42 into the left atrium 44 of theheart 12. The flexible section 26 of the shaft 25 can then be moved oradjusted to the activated configuration, as described above.

As shown in FIGS. 4B-4C, the delivery catheter 16 can then be rotated inthe direction shown by arrow 58, causing the distal end 28 of the shaft25 to move laterally over the posterior leaflet 50 towards thecoaptation edges of the leaflets 50, 52. The distal end 28 of the shaft25 can then be positioned under the anterior leaflet 52 (e.g., desirablynear the A3 and P3 regions of the leaflets, as identified by Carpentiernomenclature) such that the lumen 32 of the shaft 25 opens into theventricular side of the anterior leaflet 52, while the helically curvedportion 48 and the “U”-shaped portion 46 remain on the atrial side ofthe leaflets 50, 52, as shown in FIGS. 4D-4E.

With the delivery catheter 16 in the position shown in FIGS. 4D-4E, thedocking device 34 can be advanced through the lumen 32 of the shaft 25such that the first ventricular coil 54 a extends from lumen 32 into theleft ventricle 40 of the patient's heart. Due to the flexible andelastic nature of the docking device 34, the docking device 34 canassume a coiled or helical configuration as it exits the lumen 32 of theshaft 25. For example, as the first ventricular coil 54 a is advancedfrom the lumen 32 of the shaft 25, the first ventricular coil 54 atracks under the leaflets 50, 52 and advances around the rigid section30 of the shaft 25, as shown in FIGS. 4F-4G. As the docking device 34 isfurther advanced through the lumen 32 of the shaft 25, the secondventricular coil 54 b also tracks under the leaflets 50, 52 and advancesaround the rigid section 30 of the shaft 25 above the first lower turn54 a, as shown in FIG. 4H.

With the ventricular coils 54 of the helical docking device 34positioned under the leaflets 50, 52, the delivery catheter 16 can thenbe rotated in the direction of arrow 76 in FIG. 4I, such that the distalend 28 and lumen 32 of the shaft 25 is rotated back and again opens intothe atrial side of the leaflets 50, 52, in order to deploy the atrialcoils 56 a, 56 b from the distal end 28 of the shaft 25. The deliverycatheter 16 can also be advanced upwardly in the direction of arrow 60into the left atrium 44, to apply a small amount of tension to thedocking device against the native mitral valve as the atrial coils 56 a,56 b are deployed. Positioning the delivery catheter 16 in this mannerallows the atrial coils 56 a, 56 b to deploy on the atrial side of themitral valve 42, while the tension holds the atrial coils 56 a, 56 bspaced slightly above the native leaflets.

The atrial coils 56 a, 56 b can then be fully deployed, for example, bycontinuing to rotate the delivery catheter 16 in the direction of arrow76 to further release the docking device 34 from the lumen 32 of theshaft 25. FIG. 4J shows the first and the second coils 56 a, 56 b,respectively, extending around the delivery catheter 16 on the atrialside of the mitral valve 42. During this deployment, an axial space 62and a positive pitch between the second ventricular coil 54 b and thefirst atrial coil 56 a remains, as shown in FIG. 4J. FIG. 4K is aschematic cross-sectional view showing the docking device 34 when it isstill in a partially axially expanded state.

Fully deploying the docking device 34 from the delivery catheter 16releases the tension on the docking device 34, allowing the atrial coils56 a, 56 b to move axially downward towards the ventricular coils 54 a,54 b. The ventricular coils 54 a, 54 b may also move axially upwardtowards the atrial coils 56 a, 56 b. In this manner, the docking device34 moves toward its axially compressed state, as shown in FIG. 4L. Asthe atrial coils 56 a, 56 b nest within the ventricular coils 54 a, 54b, the native leaflets 50, 52 become captured between the ventricularcoils on the ventricular side of the native leaflets and the atrialcoils on the atrial side of the native leaflets. Securing the dockingdevice 34 to the native leaflets 50, 52 with the native leafletscompressed or pinched axially and radially between the coils can assistthe docking device to better maintain its positioning relative to thenative leaflets, compared to coils that can only apply axially directedforces against the captured leaflets.

By virtue of the axially compressed state of the docking device 34 andby deploying the atrial coils 56 a, 56 b in the manner described, thedocking device 34 can also achieve a relatively high anchoring position(e.g., the second atrial coil 56 b can be positioned close to or higherthan the annulus of the mitral valve 42). Positioning the docking deviceat a relatively high position can, for example, help avoid or reduceleft ventricle outflow tract (LVOT) occlusion, as well as chordae and/orleft ventricle damage or leakage due to insufficient leaflet coaptation.

Once the docking device 34 is secured to the native leaflets 50, 52, thedelivery catheter 16 can be removed from the patient's heart 12, forexample, by straightening the flexible section 26 of the shaft 25 andretracting the delivery catheter 16 through the lumen 22 of theintroducer 14. The flexible section 26 of the shaft 25 can, for example,be straightened by advancing a rigid rod through the lumen 32 of theshaft 25 into the flexible section 26, or by adjusting one or more pullwires.

With the delivery catheter 16 removed, a prosthetic valve 36 can then beintroduced into the patient's heart 12. As shown in FIG. 4L, theprosthetic valve 36 can be mounted on an inflatable balloon 66 of aballoon catheter 64. However, the prosthetic valve 36 can be anyplastically-expandable prosthetic valve that can be mounted in aradially compressed state on an expansion mechanism of a valve deliverycatheter. Alternatively, the prosthetic valve can be a self-expandingprosthetic valve that can be retained in a radially compressed statewithin a sheath of a delivery catheter, or a mechanically-expandablevalve.

The prosthetic valve 36 can be introduced into the heart via any knowndelivery techniques or methods. In the illustrated example, the ballooncatheter 64 is inserted through the introducer 14 and into the heart 12in a transventricular approach. In other embodiments, the ballooncatheter can instead be advanced transfemorally (via a femoral arteryand the aorta), transeptally (via the superior or inferior vena cava andthrough the septal wall between the right and left atrium),transatrially (via a surgical opening in the left atrium), or by othermethods and/or via other access points.

The balloon catheter 64 is advanced distally through the introducer 14until the prosthetic valve 36 is positioned within the docking device34. Once positioning of the prosthetic valve 36 is confirmed, theprosthetic valve 36 is radially expanded to its functional size andsecured to the helical docking device 34 by inflating the balloon 66 ofthe balloon catheter 64. In the case of a self-expanding prostheticvalve, the prosthetic valve is advanced distally out of the distalopening of a sheath of the delivery catheter, or the sheath isretracted, allowing the prosthetic valve to self-expand to itsfunctional size.

The prosthetic valve 36 can be selected to have a nominal outer diameterin its radially expanded state that is slightly larger than the innerdiameter of the atrial coils 56 a, 56 b. As a result, when theprosthetic valve 36 is radially expanded to its functional configurationwithin the docking device 34, the outer surface of the prosthetic valve36 is forced radially against the inner diameter of the atrial coils 56a, 56 b, thereby radially compressively securing the prosthetic valvewithin the docking device 34.

As shown in FIG. 4M, the prosthetic valve 36 can also include a bloodimpervious outer covering or sealing member 70 (also referred to incertain embodiments as an “outer skirt”) extending over the metal frame68 of the prosthetic valve. The sealing member 70 can be made of orinclude, for example, any of various biocompatible fabrics (e.g., PET)or natural tissue (e.g., pericardium tissue). The sealing member 70 canhelp create a seal between the prosthetic valve and the docking deviceto minimize or prevent paravalvular leakage between the prosthetic valveand the docking device. Similarly, the docking device 34 can include anouter sealing layer (not shown) covering the coil wire to furtherenhance the sealing between the prosthetic valve and the docking device.

Once the prosthetic valve 36 is secured within the docking device 34,the balloon catheter 64 can be removed from the patient's heart 12 bydeflating the balloon 66 and retracting the catheter 64 from theprosthetic valve 36 and the introducer 14. The introducer 14 can then beremoved from the patient's heart 12, and the opening in the patient'sheart 12 can be closed.

FIGS. 5A-5E show a method of implanting the helical docking device 34 atthe native mitral valve 42 of a patient's heart 12 with a deliveryapparatus 200, according to another embodiment that uses a transseptaltechnique.

The delivery apparatus 200 includes an outer catheter 202 and a flexibledelivery catheter 204. The outer catheter 202 can have an axiallyextending shaft 206 and a lumen 208, which extends co-axially throughthe shaft 206. Through the lumen 208 of the outer catheter 202, variousother components (e.g., delivery catheter 204, device 34, etc.) can beintroduced into the patient's heart 12.

The delivery catheter 204 of the delivery apparatus 200 forms orincludes an elongate shaft 210. The shaft 210 has a flexible section 212extending along a distal portion of the shaft 210, a relatively morerigid section 214 located adjacent and proximal to the flexible section212, and a lumen 216 that extends the length of the shaft 210.

The flexible section 212 of the shaft 210 can be positioned or adjustedbetween a first, delivery configuration and a second, activatedconfiguration. Although not shown, in the delivery configuration, theflexible section 212 is substantially straight, allowing the flexiblesection 212 to easily pass through the lumen 208 of the outer catheter202. As best shown in FIG. 5A, in the activated configuration, thedelivery catheter forms a helically curved portion 218. The helicallycurved portion 218 has a proximal section 220 that curves radially awayfrom the shaft 210 in a plane that is substantially perpendicular to theshaft 210, and a distal tip portion 222 that is angled downwardly awayfrom the plane of the proximal section 220. The activated configurationcan help position the helical docking device 34 during the implantationprocedure, as further described below.

The shaft 210 can be formed from similar materials and can have aconstruction similar to shaft 25 described above, to effecttransitioning of the shaft from the delivery configuration to theactivated configuration.

In the transseptal technique shown in FIGS. 5A-5E, first, a distal end224 of the outer catheter 202 is inserted through a femoral vein and theinferior vena cava 90, and into the right atrium 92. The interatrialseptum 94 is then punctured and the outer catheter 202 is passed intothe left atrium 44, as can be seen in FIG. 5A. Alternatively, the rightatrium 92 can be accessed through the superior vena cava via otheraccess points of the patient's vasculature. The outer catheter can havea steerable or pre-curved distal end portion to facilitate steering ofthe outer catheter 202 into the left atrium.

With the delivery catheter 204 in the delivery configuration, thedelivery catheter 204 is then advanced through the lumen 208 of theouter catheter 202, such that distal tip 222 of the delivery catheter204 is positioned in the left atrium 44. The delivery catheter 204 isthen further advanced through the mitral valve 42 and into the leftventricle 40. As shown in FIG. 5A, the flexible section 212 of thedelivery catheter 204 can then be moved into the activatedconfiguration, for example, by allowing the flexible section 212 toassume its shape-set shape or by actively bending the flexible section212, for example, by using methods similar to those discussed withrespect to the delivery catheter described in FIGS. 4A-4M.

With the delivery catheter 204 in this position, the docking device 34can be advanced through the lumen 216 such that the first ventricularcoil 54 a extends from lumen 216 into the left ventricle 40. Due to theflexible and elastic nature of the docking device 34, the docking device34 can assume a coiled or helical configuration as it exits the lumen216. For example, as the first ventricular coil 54 a is advanced fromthe lumen 216, the first ventricular coil 54 a tracks under the leaflets50, 52, as best shown in FIG. 5B. As the docking device 34 is furtheradvanced through the lumen 216, the second ventricular coil 54 b alsotracks under the leaflets 50, 52 and above the first ventricular turn 54a, as shown in FIG. 5C.

With the ventricular coils 54 of the helical docking device 34positioned under the leaflets 50, 52, the delivery catheter 204 can thenbe retracted upwardly in the direction of arrow 226 back into the leftatrium 44 (see, e.g., FIG. 5D). Retracting the delivery catheter 204upwardly in the direction of arrow 226 allows the atrial coils 56 a, 56b to be deployed on the atrial side of the mitral valve 42, and alsoapplies a small amount of tension to the docking device as the atrialcoils 56 a, 56 b are deployed to hold the atrial coils slightly spacedabove the native leaflets.

The atrial coils 56 a, 56 b can then be deployed by further advancingthe docking device 34 through the lumen 216, for example, by rotatingthe delivery catheter 204 in the opposite direction of the direction ofextension of the coils. FIG. 5D shows the first and the second atrialcoils 56 a, 56 b positioned on the atrial side of the mitral valve 42.The upward tension from the delivery catheter 204 causes the atrialcoils 56 a, 56 b to deploy higher than the ventricular coils 54 a, 54 b,and creates an axial space 62 and a positive pitch between the secondventricular coil 54 b and the first atrial coil 56 a, as shown in FIG.5D.

Fully deploying and releasing the docking device 34 from the deliverycatheter 204 releases tension on the docking device 34, allowing theatrial coils 56 a, 56 b to move axially downward towards the ventricularcoils 54 a, 54 b, where the ventricular coils 54 a, 54 b may also moveaxially upward towards the atrial coils 56 a, 56 b, to move the dockingdevice to the axially compressed state, as shown in FIG. 5E. As theatrial coils 56 a, 56 b nest within the ventricular coils 54 a, 54 b,the native leaflets 50, 52 become captured between the ventricular coilson the ventricular side of the native leaflets and the atrial coils onthe atrial side of the native leaflets.

Once the docking device 34 is secured to the native leaflets 50, 52, thedelivery catheter 204 can be removed from the patient's heart 12, forexample, by straightening the flexible section 212 and retracting thedelivery catheter 204 back through the lumen 208 of the outer catheter202.

With the delivery catheter 204 removed, a prosthetic valve (e.g.,prosthetic valve 36) can then be introduced into the patient's heart 12using known techniques or methods, for example, as described above withrespect to FIGS. 4L-4M. The prosthetic valve can then be secured withinthe docking device 34, also similarly as described above.

Once the prosthetic valve is secured within the docking device 34, theprosthetic valve delivery apparatus and outer catheter 202 can beremoved from the patient's body, and the opening in the patient's septum94 and right femoral vein can be closed.

FIGS. 6A-6D show a docking device 80, according to a second embodiment.The docking device 80 includes three ventricular coils 82 a, 82 b, 82 cand three atrial coils 84 a, 84 b, 84 c. As can be seen, the atrialcoils 84 a, 84 b, 84 c have an inner diameter that is greater than theinner diameter of the ventricular coils 82 a, 82 b, 82 c.

Like the embodiment of FIGS. 2A-3B, the docking device 80 is axiallyexpandable, for example, when tension is applied to one or both ends ofthe docking device 80, and is axially compressible, for example, whentension is released from the docking device. FIGS. 6A-6B show thedocking device in an axially expanded state, where all the coils extendin a same axial direction and have a positive pitch in this axialdirection with respect to adjacent coils.

FIGS. 6C-6D show the docking device 80 fully deployed and in an axiallycompressed state, for example, after tension is released from thedocking device 80. In this state, the axial coils and the ventricularcoils move towards one another, until at least some of the ventricularcoils are nested within the axial coils. In addition, the thirdventricular coil 82 c is positioned upstream of the first atrial coil 84a, and can therefore be considered to have a negative pitch with respectto the first atrial coil 84 a.

By virtue of the docking device 80 assuming the axially compressed stateshown in FIGS. 6C-6D, the native mitral valve leaflets 50, 52 becomecaptured and pinched between the atrial coils 84 a, 84 b, 84 c and theventricular coils 82 a, 82 b, 82 c.

FIG. 6D shows a final configuration where a prosthetic valve 36 issecured in the docking device 80. In some embodiments, a portion of thenative leaflets 50, 52 is pinched or otherwise held between the innercoils (the ventricular coils 82 a, 82 b, 82 c in the illustratedembodiment) and the sealing member 70 of the prosthetic valve 36,thereby enhancing the seal between the docking device 34 and theprosthetic valve 36.

FIGS. 7A-7C show a docking device 300 according to a third embodiment.In the illustrated embodiment, the docking device 300 has oneventricular coil 302 and one atrial coil 304. Similar to the embodimentof FIGS. 2A-3B, the inner diameter of the atrial coil 304 is less thanthe inner diameter of the ventricular coil 302, allowing the atrial coil304 to nest with the ventricular coil 302 in the compressed state,similarly as described above with respect to other embodiments. However,unlike the first and second embodiments, the docking device 300 is madeof a flat strip of material having a rectangular cross-section. Having adocking device with only one ventricular coil and one atrial coil can,for example, leave more of the native leaflets 50, 52 free (i.e.,uncaptured by the docking device 300) in the compressed state, as bestshown in FIG. 7C, which for example, can in turn advantageously improvethe native leaflets' ability to perform their ordinary function (i.e.,opening and closing of the valve during the diastolic and systolicphases of heart contraction, respectively) during the implantationprocedure and after the docking device 300 is deployed. Providing asingle ventricular coil and a single atrial coil can also, for example,reduce the complexity of the implantation procedure and allow for a morerobust design. As can be seen in FIG. 7C, in the compressed state, whenthe atrial coil 304 is nested inside the ventricular coil 302, theatrial coil 304 can be arranged to be substantially coplanar with or atapproximately a same axial position as the ventricular coil 302, suchthat rather than assuming a negative pitch, the coils in this embodimentcan be viewed as being arranged with a zero pitch.

FIGS. 8A-8C show a docking device 400 according to a fourth embodiment.In the illustrated embodiment, the docking device 400 includes threeventricular coils 402 a, 402 b, 402 c and three atrial coils 404 a, 404b, 404 c. Like the embodiment of FIGS. 7A-7C, the docking device 400 ismade of a flat wire having a rectangular cross-section. In addition, theventricular coil 402 a has a smaller inner diameter than the ventricularcoil 402 b, and the ventricular coil 402 b has a smaller inner diameterthan the ventricular coil 402 c. The atrial coil 404 a has a smallerinner diameter than the atrial coil 404 b, and the atrial coil 404 b hasa smaller inner diameter than the atrial coil 404 c. In this manner, theatrial coils 404 a, 404 b, 404 c collectively have a conical shapetapering from the uppermost atrial coil 404 c to the lowermost atrialcoil 404 a, and the ventricular coils also collectively have a conicalshape tapering from the uppermost ventricular coil 402 c to thelowermost ventricular coil 402 a.

As best shown in FIG. 8B, the ventricular coil 402 a and the atrial coil404 a have substantially similar inner diameters, the ventricular coil402 b and the atrial coil 404 b have substantially similar innerdiameters, and the ventricular coil 402 c and the atrial coil 404 c havesubstantially similar inner diameters. As such, when the device 400moves from the axially expanded state as shown in FIGS. 8A-8B to theaxially compressed state as shown in FIG. 8C, the respective ventricularcoils 402 a, 402 b, 402 c can at least partially radially overlap withthe atrial coils 404 a, 404 b, 404 c, in a manner similar to a conewithin a cone.

Due to the conical shape of the coils, the ventricular coils 402 a, 402b, 402 c and atrial coils 404 a, 404 b, 404 c can axially interlock in awedge-like manner with the native leaflets 50, 52 captured between theventricular coils 402 a, 402 b, 402 c and the atrial coils 404 a, 404 b,404 c, as shown in FIG. 8C. This wedge-like interlocking can, forexample, enhance the retention force applied by the docking device 400to the native leaflets 50, 52. The conical shape can also, for example,allow the device 400 to better track the natural curved-shape of thenative leaflets 50,52. As such, the docking device 400 can be lesstraumatic to the native leaflet tissue. In addition, the conical shapecan, for example, enable better self-alignment of the ventricular coilsand the atrial coils as the coils move from the axially expanded stateto the axially compressed state.

FIGS. 9A-9C show an embodiment of a portion of a delivery catheter 100,similar to guide catheter 16 discussed above, configured for deliveringa docking device. The delivery catheter 100 in the illustratedembodiment includes an elongate shaft 102 and a pull wire 104. The shaft102 has a centrally disposed and axially extending lumen 106, and thepull wire 104 extends co-axially through the lumen 106 of the shaft 102.The distal end 108 of the pull wire 104 can be fixedly secured orattached (e.g., with an adhesive, welding, etc.) to the distal end 110of the shaft 102. The shaft 102 of the guide catheter 100 has differentaxial sections, including a flexible, distal section 112 and arelatively more rigid section 114 (e.g., as seen in FIG. 9C) locatedadjacent and proximal to the flexible, distal section 112.

As shown in FIGS. 9A-9B, near the distal end 110 of the shaft 102, theflexible section 112 has a first plurality of circumferentiallyextending, axially spaced slots 116 on one side of the shaft and aplurality of diagonally or generally helically extending slots 118 on anopposing side of the shaft. The circumferential slots 116 can be axiallyspaced apart and angularly offset from each other, such that the slotsare spaced relative to each other in a spiral or helical configuration,as best shown in FIG. 9A. The diagonal slots 118 can extend axially andcircumferentially in a helical shape, as best shown in FIG. 9B. Thecircumferential slots 116 are generally diametrically opposed to thediagonal slots 118 on the shaft 102.

The flexible section 112 of the shaft 102 also has a second plurality ofcircumferential slots 120 and a third plurality of circumferential slots122, which are positioned proximally relative to the first plurality ofcircumferential slots 116 and the diagonal slots 118. The secondplurality of circumferential slots 120 are axially spaced apart andangularly aligned with each other, as best shown in FIG. 9A. The thirdplurality of circumferential slots 122 are also axially spaced apart andangularly aligned with each other, as best shown in FIG. 9B. The slots120 and the slots 122 can also be formed in diametrically opposed sidesof the shaft 102 relative to one another.

The shaft 102 can be formed, for example, from a tube. The slots 116,118, 120, 122 can be formed, for example, by laser cutting the tube. Inparticular embodiments, the shaft 102 can be formed from an elasticallydeformable, shape-memory material such as Nitinol.

Due to the manner in which the slots 116, 118, 120, 122 are positionedrelative to each other and the widths of the slots, pulling on theproximal end of the pull wire 104 causes the flexible section 112 of theshaft 102 to deform into an activated configuration, as shown in FIG.9C. Releasing tension on the pull wire 104 allows the flexible sectionto return to its undeformed, straight configuration.

FIG. 9C shows the activated configuration, in which the flexible section112 of the shaft 102 forms a first, “U”-shaped curved section 124 and asecond, helically curved section 126. The slots 120 are positioned alongthe inner radius of the curved section 124 and the slots 122 arepositioned along the outer radius of the curved section 124. The slots116 are positioned along the inner radius of the curved section 126 andthe slots 118 are positioned along the outer radius of the curvedsection 126. In the illustrated embodiment, the first curved section 124forms a 180-degree bend at the end of the rigid section 114 and has adistal section that extends substantially parallel to the rigid section114. The second curved section 126 has a proximal section 126 a thatcurves radially away from the first curved section 124 in a plane thatis substantially perpendicular to the first curved section 124 and adistal tip portion 126 b that is angled downwardly away from the planeof the proximal section 126 a. The shape of the curved sections 124, 126can help position a helical docking device relative to the nativeleaflets 50, 52 when the docking device is deployed from the lumen 106of the shaft 102, for example, similarly as described above with respectto the delivery catheter 16.

The slots 118, 122 facilitate bending by reducing the strain on theouter radius of the curved sections 124, 126. The slots 116, 118, 120,122 can also help avoid kinking of the shaft 102, thereby allowingdevices (e.g., a docking device 34) to pass more easily through thelumen 106 of the shaft when the flexible section 112 is in the activatedconfiguration.

Although not shown, the guide catheter 100 can have multiple radiallayers. For example, the shaft 102 of the guide catheter 100 can have apolymeric outer cover (e.g., PTFE). The guide catheter 100 can alsoinclude an alloy or metal mesh or weave (e.g., braided Nitinol). Inaddition, the interior of the guide catheter can be lined with alubricious material (e.g., PTFE) to allow other devices and componentsto pass more easily through the lumen 106 of the shaft 102.

It should be noted that the devices and apparatuses described herein canbe used with other placement techniques (e.g., transatrial, open heart,etc.). It should also be noted that the devices described herein (e.g.,the helical docking devices and prosthetic valves) can be used incombination with other delivery systems and methods. For example,additional information regarding devices, delivery systems, and methodscan be found in U.S. Provisional Patent Application No. 62/088,449 andInternational Patent Application No. PCT/IB2013/000593 (WIPO PublicationNo. 2013/114214), which are incorporated by reference herein in theirentirety.

For purposes of this description, certain aspects, advantages, and novelfeatures of the embodiments of this disclosure are described herein. Thedisclosed methods, apparatuses, and systems should not be construed aslimiting in any way. Instead, the present disclosure is directed towardall novel and nonobvious features and aspects of the various disclosedembodiments, alone and in various combinations and sub-combinations withone another. The methods, apparatuses, and systems are not limited toany specific aspect or feature or combination thereof, nor do thedisclosed embodiments require that any one or more specific advantagesbe present or problems be solved.

Although the operations of some of the disclosed embodiments aredescribed in a particular, sequential order for convenient presentation,it should be understood that this manner of description encompassesrearrangement, unless a particular ordering is required by specificlanguage. For example, operations described sequentially can in somecases be rearranged or performed concurrently. Moreover, for the sake ofsimplicity, the attached figures may not show the various ways in whichthe disclosed methods can be used in conjunction with other methods.Additionally, the description sometimes uses terms like “provide” or“achieve” to describe the disclosed methods. These terms are high-levelabstractions of the actual operations that are performed. The actualoperations that correspond to these terms can vary depending on theparticular implementation and are readily discernible by one of ordinaryskill in the art.

In view of the many possible embodiments to which the principles of thedisclosure can be applied, it should be recognized that the illustratedembodiments are only preferred examples of the invention and should notbe taken as limiting the scope of the disclosure. Rather, the scope ofthe disclosure is defined by the following claims.

The invention claimed is:
 1. A system for securing a prosthetic heartvalve at a native heart valve of a heart of a patient, the systemcomprising: a docking device comprising a first set of one or more coilsand a second set of one or more coils, and a central axis extendingthrough the first set of one or more coils and the second set of one ormore coils; and a prosthetic heart valve configured to be held in thedocking device; wherein the docking device is configured to assume anaxially expanded state wherein the entire first set of one or more coilsis positioned on a first side of the second set of one or more coilsrelative to the central axis; and wherein the docking device isconfigured to assume an axially compressed state wherein a first coil ofthe first set of one or more coils is positioned on a second side of atleast a portion of the second set of one or more coils opposite to thefirst side relative to the central axis.
 2. The system of claim 1,further comprising a delivery catheter, wherein the delivery catheter isconfigured to deploy the docking device at the native heart valve. 3.The system of claim 1, wherein the first set of one or more coils has afirst inner diameter, and the second set of one or more coils has asecond inner diameter different from the first inner diameter.
 4. Thesystem of claim 1, wherein the first set of one or more coils comprisesat least two coils and the second set of one or more coils comprises atleast two coils.
 5. The system of claim 4, wherein at least one of thecoils of the first set of one or more coils is positioned relative tothe central axis between two coils of the second set of one or morecoils when the docking device is in the compressed state.
 6. The systemof claim 1, wherein the first set of one or more coils is configured tobe positioned on a ventricular side of a native mitral valve, and thesecond set of one or more coils is configured to be positioned on anatrial side of the native mitral valve.
 7. The system of claim 1,wherein the first set of one or more coils and the second set of one ormore coils each comprises a shape-memory material.
 8. The system ofclaim 1, wherein the first set of one or more coils is positionedradially inward relative to the second set of one or more coils when thedocking device is in the compressed state.
 9. The system of claim 8,wherein the first set of one or more coils is configured to exert aradially outwardly directed force against the second set of one or morecoils when the device is in the compressed state.
 10. The system ofclaim 1, wherein, when in the axially expanded state, the entire firstset of one or more coils and the entire second set of one or more coilshave a positive pitch relative to each other, and when in the axiallycompressed state, at least a portion of the first set of one or morecoils has a negative pitch relative to the second set of one or morecoils.
 11. A method of using the system of claim 1 to treat a nativevalve of a heart of a patient, the method comprising: positioning thefirst set of one or more coils on a first side of the native valve;positioning the second set of one or more coils on a second side of thenative valve, such that the entire first set of one or more coils ispositioned on a first side of the second set of one or more coilsrelative to a central axis of the device; and transitioning the dockingdevice to a position where the first coil of the first set of one ormore coils is positioned on a second side of at least a portion of thesecond set of one or more coils opposite to the first side relative tothe central axis.
 12. The method of claim 11, further comprisingimplanting the prosthetic heart valve in the device.
 13. The method ofclaim 12, wherein implanting the prosthetic heart valve comprisespositioning the prosthetic heart valve in the device when the prostheticheart valve is in a radially compressed state, and radially expandingthe prosthetic heart valve such that a radial pressure is appliedbetween the prosthetic heart valve and the device to anchor theprosthetic heart valve in the device.
 14. The method of claim 11,wherein after transitioning the device, the first coil is configured tobe positioned between two coils of the second set of coils relative tothe central axis.
 15. The method of claim 11, wherein the first set ofone or more coils and the second set of one or more coils of the deviceare configured to radially compress leaflets of the native valve. 16.The method of claim 11, wherein positioning the first set of one or morecoils comprises advancing a distal end of a delivery catheter into theheart, and deploying the first set of one or more coils from thedelivery catheter on the atrial side of the native valve, and whereinpositioning the second set of one or more coils comprises deploying thesecond set of one or more coils on the ventricular side of the nativevalve.
 17. The method of claim 16, wherein positioning the first set ofone or more coils further comprises maintaining an axial tension on thedocking device when the docking device is being deployed from thedelivery catheter, such that the docking device is at least partiallyaxially expanded, and wherein transitioning the docking device comprisesreleasing tension on the docking device to allow the device to compressaxially.